MathBench > Measurement

Calculating Molar Weight

What about more complicated molecules?

How about a mole of water? You know that the formula for water is H2O. So, if you broke all the bonds, a mole of water would actually contain TWO moles of hydrogen and ONE mole of oxygen.


sailboat in water You can then use the periodic table to determine how much each of those weighs:

total weight = 2 x Hydrogen + 1 x Oxygen

total weight = 2 x 1.008g + 1 x 15.99g

total weight = 18.006g

So a mol of water is about one swallow.